The Rosetta Stone is a slab of granitoid stone featuring a written decree issued in 196 B.C. by a group of Egyptian clergy and Egypt’s ruler, Ptolemy V, attesting to his generosity and devoutness. The decree is written in three ways: hieroglyphics, which were used mainly by priests; Demotic, a somewhat simpler script used for everyday purposes; and ancient Greek.

The use of hieroglyphics died out after the 4th century and the writing system became an enigma to scholars, making the stone an essential tool in helping researchers understand the long-forgotten language.

It wasn't until the 19th century—two thousand years after its creation—that the Rosetta Stone helped scholars crack the code of hieroglyphics. French army engineers who were part of Napoleon Bonaparte’s Egypt campaign discovered the stone slab in 1799 while repairing a fort near the town of Rashid (Rosetta).

The artifact was originally displayed in a temple, possibly near the ancient town of Sais. Centuries later, it was moved to Rosetta and was used in the construction of Fort Julien, where it was eventually uncovered by the French. The Rosetta Stone came into the possession of the British after they defeated the French in Egypt in 1801.

British scientist Thomas Young, who began studying the Rosetta Stone’s texts in 1814, made some initial progress in analyzing its hieroglyphic inscription. Young surmised that the cartouches—hieroglyphs enclosed in ovals—contained the phonetic spellings of royal names, including Ptolemy, referenced in the Greek inscription.

Ultimately, it was French linguist Jean-Francois Champollion who deciphered the Rosetta Stone and cracked the hieroglyphic code. Between 1822 and 1824, Champollion showed that hieroglyphics were a combination of phonetic and ideographic signs rather than just symbolic picture writing that didn’t also represent sounds of language, as earlier scholars had suspected. For his discoveries, Champollion is heralded as the founding father of Egyptology.

Today, the Rosetta Stone, which measures about 44 inches tall and 30 inches wide, is housed in the British Museum in London, where it’s been since 1802, except for a temporary re-location for safekeeping during World War I to an off-site, underground spot. There have been repeated calls for it to be repatriated to Egypt.